In recent years, superconductive materials, including superconducting ceramic materials, have been proposed for use in many diverse applications. These uses include high speed computers, magnet-intensive technologies, transmission of electrical power, transportation and recreation, among others.
Since the discovery that ceramic systems can be superconducting above the liquid nitrogen temperature, a great deal of work has been done to prepare superconducting samples by a variety of methods. These methods include, but are not limited to, powder processing, melt spinning and various film deposition techniques. An appropriate combination of heat treatments of these samples makes them superconducting. The most commonly used method of heat treatment is conventional heating, wherein different parameters are varied to obtain optimum results.
Despite the recognition of the importance of the heat treatment, heat treatment is still carried out only by conventional methods. This is a time consuming method which allows undesirable grain growth resulting in non-uniform grain size and insufficient densification. Conventional methods heat from the outside inwardly, which promotes inhomogeneity. These deficiencies can lead to poor properties of the superconducting ceramic.
Therefore, it is an object of the present invention to provide an improved method for heating a number of ceramic systems to produce superconducting ceramics.
It is a further object of the present invention to provide a process for producing superconducting ceramics which does not suffer from the disadvantages of prior processes.
It is yet another object of the present invention to provide an efficient and effective method for producing superconducting ceramics.
It is still another object of the present invention to provide a process for uniformly heating ceramic materials which results in controlled microstructure and densification.
Additional objects of the present invention will be understood by reference to the following description.